Recently, memory systems including a non-volatile memory are becoming more widely used. A solid state drive (SSD) including a NAND-type flash memory is one type of such memory system. The SSD is used as the main storage in various information processing devices.
An Atomic Write function is known as a function employed to maintain consistency of data stored in a memory system. If a data write is requested as an Atomic Write, the entire data writing must be completed, or must be cancelled even after data are received and data writing has already started. After such cancellation, the memory system is returned to a state as if no data write request was received. The Atomic Write function guarantees that the state of the memory system returns (rolls back) to a state before the data write, if the data write is cancelled before completion. The rollback of the Atomic Write function is also referred to as cancellation of the Atomic Write. According to the Atomic Write function, if a data write is requested as Atomic Write, the data writing is entirely committed or entirely cancelled.